The Transcaval AngioVac Aspiration of a Left Subclavian Artery Intimal Sarcoma Masquerading as Arterial Thrombosis: A Case Report.

Background and Clinical Significance: Intimal sarcoma is a rare, aggressive malignancy of the large arteries that grows within the vessel lumen and frequently mimics thromboembolic disease, leading to diagnostic delay. Flow restoration and tissue biopsy are both difficult if the tumour occupies a technically demanding arterial segment, which is further aggravated if conventional large-bore arterial access is precluded by peripheral arterial disease. Case Presentation: A 66-year-old woman with multiple cardiovascular risk factors presented with subacute left upper-limb ischaemia and painless digital cyanosis (embolic phenomena) that had progressed despite therapeutic anticoagulation. Computed tomography angiography demonstrated a sub-occlusive filling defect extending from the origin of the left subclavian artery towards the aortic arch, initially interpreted as thrombus. There were no clear signs of malignant disease, despite differential screenings. Multiple on- and off-site surgical consultations were done, but the patient was repeatedly rejected for operation due to disease characteristics and high surgical risk. Severe iliofemoral peripheral arterial disease precluded usual transfemoral arterial delivery of a large-bore system, so the subclavian mass was aspirated using a 22/26-French sheath and extracorporeal aspiration system (AngioVac System (AngioDynamics)) delivered through percutaneous transcaval (caval-aortic) access, under cerebral embolic protection. Repeated aspiration runs with mechanical snare augmentation achieved substantial debulking, angiographic normalisation of flow and abolition of the invasive pressure gradient, without injury to the target artery. The caval-aortic tract was eventually closed with an occluder device. Histopathology of the aspirate revealed a malignant spindle-cell mesenchymal neoplasm consistent with intimal sarcoma. Staging subsequently demonstrated metastatic disease, and the patient proceeded to covered-stent maintenance of subclavian patency and first-line systemic chemotherapy. The patient is undergoing chemotherapy at 7-month follow-up, but palliation is being considered due to disease progression. Conclusions: Transcaval delivery of a large-bore aspiration system (AngioVac) is a feasible strategy to achieve both flow restoration and diagnostic tissue sampling when conventional arterial access is unavailable. Intimal sarcoma should be considered when arterial "thrombus" fails to respond to anticoagulation, particularly alongside constitutional symptoms.